2000 Dodge Neon 2.0L won't start, Help?

My 2000 dodge neon 2.0l 4cyl won't start. It will turn over but just won't start. At some moments it will start up if I floor it but then turns off right away. I have replaced the fuel pump/filter and they are both functioning right and I have also replaced the camshaft censor, I was thinking about replacing the O2 censor and crankshaft sensor but my brother advised me that the car would still start up if the O2 and crankshaft censors were bad. Also right before it stopped turning on while I was driving it would struggle to go and would stall if I stopped at any red light or stop sign unless I kept revving the engine while holding the break. Any ideas on what to do, I only have about $300 to throw into this and really need to get this fixed ASAP or there is no way I will be able to get back to work.

Any overheating issues before any of this happened? It wouldn't start at all if you had a bad CKP, you wouldn't get spark or fuel. I've never seen a O2 sensor that would cause a car to start and stall either..But ANYTHING is possible I suppose.

Perhaps a BIG vacuum leak? Dirty throttle body? Leaky Injector(s)?

Just a few things.. If I were you I would take it to a professional because chances are you'll spend more money throwing parts at it then it would take someone to diagnose it.

Actually it was overheating before all of this happened and the idle was REALLY bad but I just figured the overheating was the thermostat because when I would turn the heater on it would cool down. There is a vacuum leak somewhere because I could hear it when the car was functioning but as for the throttle body and injectors I am not sure. Well there is a spark and there is fuel getting to the engine so I guess it isn't the CKP. Thanks for the help, I am going to get a diagnostic done and will post what codes come up.

Was this all worth $350 I mean the car runs all right now but the battery light came up on the dashboard and I think it might be the alternator but I'm not sure (Any idea of what this might cost total??)